KR101688904B1 - Method, apparatus and storage medium storing program for jetting liquid material - Google Patents

Abstract

An object of the present invention is to provide a liquid material discharging method, apparatus, and program capable of stabilizing a liquid material (droplet) shape and discharging state of a liquid material to be discharged (discharged) and improving the discharging accuracy do. According to the present invention, there is provided a liquid metering apparatus comprising a metering section for metering a liquid material, a discharge port communicating with one end of the metering section, and a plunger for slidingly moving the inner wall of the metering section, And a discharging step of discharging the liquid material from the discharging opening by moving the plunger in the direction of the discharging port and then stopping the discharging of the liquid material, And a preliminary operation of moving the plunger without discharging the liquid material, so that the speed of the plunger in the discharging step is controlled to be constant.

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid material ejecting method, an apparatus, and a storage medium storing a program,

The present invention provides a liquid material discharge method, apparatus and program for discharging a liquid material by moving a plunger slidingly moving in a metering section in communication with a nozzle having a discharge port (desired discharge port) by a desired amount, To an ejection method, an apparatus, and a program for repeatedly ejecting a liquid material quantitatively (quantitative) without causing unevenness in the ejection amount by controlling the operation of the ejection mechanism.

In this specification, the term " flying " means that the liquid material is separated from the discharge port before the liquid material comes into contact with the object to be coated.

There is a discharge device called a plunger pump (or syringe pump). This kind of ejecting apparatus is widely used in a scene in which it is necessary to eject a certain amount of liquid material accurately, such as an ODF process in liquid crystal panel manufacturing.

The plunger pump is roughly described as a discharging device for discharging a liquid material by a discharge port by advancing and moving a plunger that moves closely in the metering section. The volume of the discharged plunger is adjusted to a discharge port And the plunger can be moved so as to advance at a high speed and then abruptly stopped so as to discharge the liquid material from the discharge port so as to emit the liquid material.

In the plunger pump, since the plunger moves close to the inside of the metering portion, the sealing portion is mostly provided at the contact portion. Since this sealing portion is a portion where sliding movement occurs, abrasion or deformation occurs, and various adverse effects are given to the pump. For example, when worn, contamination is caused to contaminate the liquid material, and it is necessary to frequently replace the liquid material. On the other hand, when the plunger is deformed, the plunger is moved in spite of stopping the operation of the plunger, so that the excess liquid material is discharged.

So far, various techniques have been proposed for conducting the research on the sealing portion. For example, Patent Document 1 discloses a coating apparatus comprising a liquid transfer pump for guiding a coating liquid to a mouthpiece, wherein a sealing member used as a liquid transfer pump is made of a flexible material Shaped body, the plunger is covered by the body portion of the cap-shaped body while the opening end of the cap-shaped body is fixed on the inner peripheral surface of the cylinder, and the U-shaped vent formed by folding downward from the gap between the cylinder and the plunger Discloses a technique for sealing a gap by a bent portion.

Patent Document 2 discloses a dispenser provided in an annular groove portion formed at a tip end portion of a plunger and having an O-ring slidable along the inner wall surface of the syringe body, And the side wall of the annular groove portion is spaced apart from the side wall of the annular groove portion so that the side portion of the O-ring contacts, elastically displaces and compressively deforms as the plunger is pushed, And a plurality of convex portions or grooves for guiding the back suction of the contents are formed by sliding the plunger in a direction opposite to the direction in which the plunger is pushed in. Technology is disclosed.

Japanese Patent Application Laid-Open No. 2006-281091 Japanese Patent Application Laid-Open No. 2008-18351

As described above, various studies have been made on the plunger in the prior art, but this technique has not been able to improve the discharge amount accuracy per discharge when repeatedly discharging a plurality of times. That is, even if the plunger is operated for discharging, the discharging amount to be discharged differs for each operation, and the accurate discharging amount can not be discharged, and the discharging amount is uneven.

If unevenness is caused in the amount of ejection, when the liquid material is ejected from the ejection orifice such as a nozzle, it is divided into a plurality of portions and scattered, thereby causing defects in the shape of the droplets (droplets) .

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a liquid material discharge method, apparatus, and program capable of stabilizing the droplet shape and discharge state of the liquid material to be discharged and improving the discharge accuracy.

The inventor of the present invention verified that the irregularities in the amount of discharge occur by establishing a hypothesis that the frictional resistance acting on the sliding portion of the plunger is caused by the fact that the plunger is in operation and not in operation. The frictional resistance between the plunger and the inner wall of the metering portion includes static friction generated when the plunger is shifted from the stopped state to the operating state and dynamic friction generated during operation of the plunger. It is assumed that the frictional resistance received by the plunger changes abruptly immediately after the start of movement of the plunger from the static friction to the dynamic friction. As a result, it has been found that the operation of the plunger is unstable because the movement amount or speed of the plunger is not constant because the operation of the plunger does not follow the operation of the driving source such as the motor or the air cylinder. Further, it has been found that there is a problem that the operation is not constant with respect to the command from the control apparatus, because the driving source itself is influenced by a change in frictional resistance of the plunger.

These problems can not be solved by the prior art method of performing the study on the sealing portion of the plunger.

The present inventor has found that the problem can be solved by paying attention to the operation of the plunger, in particular, the time variation of the plunger speed within one discharging operation, and by improving the stability of the plunger operation at the start of operation of the plunger. It was done.

A first aspect of the present invention is directed to a liquid container comprising a metering section for metering a liquid material, a discharge port communicating with one end of the metering section, and a plunger slidably moving with the inner wall of the metering section, A liquid material discharging method for discharging a liquid material, comprising: a charging step of charging a material; a discharging step of discharging the liquid material from the discharging opening by moving the plunger in the direction of the discharging port; And the plunger is moved without performing the preliminary operation, thereby controlling the speed of the plunger in the discharging step to be constant.

According to a second aspect of the present invention, in the first aspect, the preliminary operation includes a first operation for moving the plunger by a predetermined distance S in a direction opposite to the discharge port, and a second operation for moving the plunger in the direction of the discharge port, And a second operation for shifting by a predetermined amount.

A third invention is characterized in that, in the second invention, the predetermined distance S is set to a distance at which the plunger is accelerated to a constant speed.

The fourth invention is characterized in that, in the second or third invention, the first operation and the second operation are repeated until the discharge step is started after the filling step.

According to a fifth aspect of the present invention, in any one of the second to fourth aspects of the present invention, the first operation is characterized in that the plunger is moved under the condition that no air bubbles are generated by the outside air sucked at the discharge port .

A sixth invention is characterized in that, in the first or second invention, the preliminary operation is an operation of gently accelerating the plunger toward the discharge port.

The seventh invention is characterized in that the preliminary operation and the discharging step are carried out continuously in any one of the first to sixth aspects of the invention.

According to an eighth aspect of the present invention, there is provided an apparatus for measuring a liquid material, comprising a metering section for metering a liquid material, a discharge port communicating with one end of the metering section, a plunger slidingly moving along the inner wall of the metering section, Is a liquid material dispensing apparatus capable of carrying out the dispensing method according to any one of the first to seventh inventions.

The ninth invention is a dispensing apparatus for a liquid material comprising a table on which an object to be coated is placed, a dispensing apparatus according to the eighth invention, and a relative moving mechanism for moving the dispensing apparatus and the table relative to each other.

A tenth aspect of the present invention is directed to a liquid container comprising a metering section for metering a liquid material, a discharge port communicating with one end of the metering section, a plunger slidingly moving along the inner wall of the metering section, a drive source for driving the plunger, A program for causing a control device to execute the ejection method according to any one of the first to seventh aspects of the invention in the ejection device.

A first operation for moving the plunger by a predetermined distance S in a direction opposite to the discharge port; a second operation for moving the plunger in the direction of the discharge port by the same or equivalent distance as the distance S; And a fourth operation for moving the plunger in the direction opposite to the ejection opening by a distance equal to or equal to the distance S, and a fourth operation for moving the plunger in the direction opposite to the ejection opening by a distance equal to or equal to the distance S.

The preliminary operation may be performed only before the liquid material filled in the metering section is discharged for the first time in discharging the liquid material filled in the metering section continuously a plurality of times.

According to the present invention, it is possible to stabilize the droplet shape and discharge state of the liquid material to be discharged, and to improve the discharge accuracy by keeping the movement amount and the speed by the plunger operation constant.

1 is a graph showing time variation of each parameter when the plunger of the discharging device of the present invention performs one discharging operation.
Fig. 2 is a graph showing a time variation of each parameter when the plunger of the conventional discharge device performs one discharge operation. Fig.
3 is a schematic view of a plunger type discharge device according to the first embodiment.
4 is a schematic perspective view showing an example of a coating apparatus on which the discharging apparatus according to the first embodiment is mounted.
5 is an explanatory view for explaining (1) a method of performing a preliminary operation each time in continuous discharge in relation to the second embodiment;
Fig. 6 is an explanatory view for explaining a method of (2) fine reciprocating movement according to Embodiment 2 as a preliminary operation. Fig.
Fig. 7 is an explanatory view for explaining a method of (3) moderate acceleration as a preliminary operation according to the second embodiment. Fig.
8 is an explanatory view for explaining a method of performing the preliminary operation only for the first time in the continuous discharge (4) according to the second embodiment.
Fig. 9 is an explanatory view for explaining a method of performing (5) a large preliminary operation according to the second embodiment. Fig.

Hereinafter, a mode for carrying out the present invention will be described by taking as an example a discharge device of a type having a plunger and a nozzle having a sealing portion for slidingly moving with the inner wall of the metering portion as shown in Fig.

Fig. 1 shows a graph showing the time variation of each parameter when the plunger of the discharge device of the present invention performs one discharge operation. Fig. 2 shows a graph showing the time variation of each parameter when the plunger of the conventional discharge device performs one discharge operation. 1 and 2, the plus of the vertical axis of the graph indicates the direction of the discharge port, and the minus indicates the direction opposite to the discharge port. (A) shows the operation signal of the driving source, (b) shows the change in the movement distance of the plunger, (c) shows the time variation of the plunger speed, and (d) shows the change in the discharge amount at the ejection opening.

Hereinafter, the description will be made while comparing the two drawings in Fig. 1 and Fig.

In order to improve the discharge accuracy and stabilize the discharge amount, it is necessary to bring the displacement of the plunger operation relative to the operation signal of the drive source close to zero without limitation. Particularly, the influence of the time variation of the plunger speed on the droplet shape and the discharge state is large. In the conventional operation method shown in FIG. 2, as can be seen from the graph of the time variation of the plunger speed in (c), the time from the start of operation until the maximum speed is reached (between 0 and A) Operation is not stable. This is because the frictional resistance generated between the sealing portion of the plunger and the inner wall surface of the metering portion is affected by the change from the static friction at the start of operation to the dynamic friction at the time of operation. Since the plunger has an unstable part that does not follow the operation signal of the driving source, the discharge amount is not stable.

Therefore, in the present invention, as shown in Fig. 1, preliminary operation 1 is performed before the discharge operation so that only the dynamic friction acts during the discharge operation in order to remove the influence of change from static friction to dynamic friction.

The preliminary operation 1 is composed of a first preliminary operation 2 and a second preliminary operation 3.

First, as the first preliminary operation 2, the plunger is moved by a predetermined distance S in the direction opposite to the discharge port (0 to A). At this time, a small amount of air is sucked into the nozzle from the discharge port. This is to prevent the liquid material from being discharged by the preliminary operation 1. The distance of movement of the plunger (distance S) is determined by a predetermined experiment or the like by setting the distance required to stabilize the plunger speed.

In addition, it is preferable that the plunger movement condition in the preliminary operation be within a range in which bubbles are not generated by suction in the nozzle. Here, in order to prevent bubbles from forming, it is important that the space formed by the air sucked into the nozzle by the preliminary operation always keeps communication with the outside (outside air) through the discharge opening. The conditions such as the movement amount and the moving speed of the plunger are determined by experiment or the like in consideration of factors such as the shape of the flow path in the nozzle and the properties of the liquid material.

Next, as the second preliminary operation 3, the plunger is moved toward the discharge port direction by a distance equal to or equal to the previously set distance S (A to B). This is because the space in which the air in the nozzle that has been sucked by the above-described operation exists is filled again with the liquid material. By doing so, an accurate amount of discharge can be performed. It is also possible to smoothly shift to a subsequent discharge operation.

Then, even if the second preliminary operation 3 is finished, the plunger is not stopped or decelerated, and the operation is immediately shifted to the discharging operation (B to C). Thus, by performing the preliminary operation 1 before the discharge operation, the frictional resistance does not change from the static friction to the dynamic friction during the discharge operation, so that the operation of the plunger is stabilized and accurate discharge can be performed.

Hereinafter, the details of the present invention will be described by way of examples, but the present invention is not limited to the embodiments.

[Example 1]

(Configuration of Discharge Apparatus)

The discharging apparatus of this embodiment will be described below with reference to Fig. The liquid material used in this embodiment is a liquid crystal (viscosity = about 20 mPa · s).

3 includes a tubular metering tube 5, a plunger 6 in which the sealing portion 9 is internally connected to the metering tube 5, and a discharge port 7 The liquid container 1 is provided with a nozzle 8 for containing liquid material and a storage container 10 for storing the liquid material and the communication between the metering pipe 5 and the nozzle 8 or between the storage container 10 and the metering pipe 5 A motor 13 serving as a driving source for driving the plunger 6 by driving the screw shaft 12 and a motor 13 for controlling the operation of the valve 11 and the motor 13 And a control device 14. Further, in order to smoothly supply the liquid material, the storage container 10 is connected to a compressed gas source (not shown) through the control device 14 and is supplied with the compressed gas.

(Operation of Discharging Apparatus)

Initially, the metering tube 5 is filled with the liquid material. First, the plunger 6 slidingly moving in the metering tube 5 is caused to advance to the position closest to the switching valve 11. Then, the switching valve 11 is switched to the position where the storage container 10 and the metering pipe 5 communicate with each other, and the plunger 6 is moved backward. The liquid material in the storage container 10 flows into the metering tube 5 through the switching valve 11 and the charging is terminated when the plunger 6 retracts to the top of the metering tube 5. [

The discharge of the charged liquid material is performed by switching the switching valve 11 to a position where the metering pipe 5 and the nozzle 8 communicate with each other and advancing and moving the plunger 6 in accordance with a desired discharge amount.

The discharge operation of the plunger 6 is performed by rapidly stopping the plunger 6 by abruptly stopping the motor 13 after rapidly accelerating the motor 13 by operating the motor 13. Thereby, the liquid material in the metering tube 5 is ejected from the tip of the nozzle 8 by the inertia force given by the rapid movement and rapid stop of the plunger 6. This discharging operation is repeated, and the liquid material in the metering tube 5 is discharged a plurality of times. Here, the discharge operation by the plunger 6 is performed continuously in parallel with the preliminary operation 1 of Fig. 1 described above. In the preliminary operation 1 and the discharging operation, as the first preliminary operation 2, the plunger is moved in a direction opposite to the discharge port by a small positive distance S previously estimated, and as the second preliminary operation 3, the plunger is moved toward the discharge port in the above- S, and advances by a distance corresponding to the discharge amount in succession to the second preliminary operation 3.

When the plunger 6 reaches the position nearest to the switch valve 11, the switch valve 11 is switched to the position where the storage container 10 and the metering pipe 5 communicate with each other and the plunger 6 is retracted And the liquid material is charged again.

In this manner, a series of operations of charging the liquid material from the storage container 10 to the metering tube 5, performing the preliminary operation, and discharging the liquid material in the metering tube 5 from the nozzle 8 are repeated, .

Since the metering tube 5 of the present embodiment has a capacity to fill a positive amount of liquid material that can be continuously discharged in small quantities a plurality of times, Or may be ejected over a period of time. On the other hand, charging may be performed for each discharging operation.

In order to stop the plunger at the end of the discharging operation, by controlling the moving speed from the start of the decelerating to the stop of the plunger moving forward, the force for dividing the liquid discharged from the nozzle is controlled (See Japanese Patent No. 4183577).

(Configuration of Coating Apparatus)

Although the above-described discharge device 4 may be used alone, it may be used for a substrate to be coated, such as a glass substrate used in a liquid crystal panel manufacturing process or a printed circuit board for mounting an electronic device The work may be carried out by being mounted on a drive mechanism that moves relative to the other. Fig. 4 shows an example of a coating device on which the discharging device 4 is mounted.

The coating apparatus 15 shown in Fig. 4 includes the above-described discharging apparatus 4, a table 17 on which the substrate 16 to be coated is mounted, a discharging apparatus 4 provided with the discharging apparatus 4 An XYZ driving mechanism 18 for relatively moving the table 17 in the X, Y and Z directions from above, and a control device for controlling the operations of these. During the coating operation, the discharging device 4 is moved to a desired position on the substrate 16 by the driving mechanism 18 to perform discharging.

4, a plurality of discharging apparatuses 4 are mounted, but this is for shortening the working time for the large-sized substrate 16 by simultaneously operating the plurality of discharging apparatuses 4 at the same time. The number of the discharging devices 4 to be mounted is not limited to three as shown in Fig. 4, and may be two or less, or four or more. That is, it is a matter that is appropriately determined by the size of the substrate 16 and the limitation of the working time that can be consumed.

(Effect of Embodiment)

In the discharging apparatus for carrying out the preliminary operation of the present embodiment, it is possible to confirm a precision improvement (reduction in non-uniformity) of about 80% as compared with a conventional discharging apparatus (mechanical structure is the same) in which no preliminary operation is performed.

[Example 2]

In the second embodiment, a method of performing ejection in combination with the preliminary operation in different modes in the ejection apparatus as in the first embodiment will be described. 5 to 9 show only the time variation of the plunger speed.

(1) Method for performing preliminary operation each time in continuous discharge (Fig. 5)

Even in the case where the liquid material in the metering section is continuously discharged a plurality of times after one charging of the metering section, if the discharging interval is long or the discharging accuracy is emphasized, as shown in Fig. 5, The preliminary operation 1 is performed at the start of operation. By doing so, the discharge precision of each of the counters is improved, and the unevenness between the respective discharges can also be reduced.

(2) Method for making minute reciprocating movement as a preliminary operation (Fig. 6)

The plunger 6 normally stops when it is not performing the discharging operation. Thus, as shown in Fig. 6, the micro-reciprocating movement 23 is repeated at the portion corresponding to the stopping time so as not to be stopped. That is, since it is always in a moving state, there are few portions where the frictional resistance changes, and stable and accurate discharging is possible. This is effective when the number of ejection is small or when the ejection interval is long.

(3) Method of making gentle acceleration as a preliminary operation (Fig. 7)

When the operation of moving the plunger 6 in the direction opposite to the discharge port 7 is performed, a small amount of air is sucked from the discharge port 7. Although it is said that the same distance is moved toward the direction of the discharge port 7 by the following operation, it may be influenced. 7, the plunger is accelerated (accelerated) in the direction of the discharge port 7 (reference numeral 24) in a portion where the plunger does not move in the direction opposite to the discharge port 7 but starts the discharge operation, So that the portion where the frictional resistance changes does not affect the ejection. By doing so, the effect of reducing the influence that the friction resistance changes due to the inhalation of air from the discharge port 7 is obtained.

(4) Method for performing the preliminary operation for the first time in the continuous discharge (Fig. 8)

The preliminary operation 1 of the present invention is basically performed every one ejection operation as shown in the embodiment. However, in the case of continuously discharging a plurality of times, if the discharging interval is short, the portion changing from static friction to dynamic friction between the stop of one discharging operation and the next discharging operation is reduced or substantially eliminated It was found experimentally. Thus, as shown in Fig. 8, the preliminary operation 1 is performed only at the start of the first discharge 19 in the series of plural discharges, and the preliminary operation 1 is not performed after the second discharge 20. By doing so, the time required for the preliminary operation 1 after the second discharge 20 can be shortened, and the operation can be performed more efficiently. This is an effective method when speed is important. Whether or not to perform the operation according to the present embodiment is determined by the surface state of the inner surface of the metering tube 5 or the sealing portion 9, the force of the sealing portion 9 pressing the inner surface of the metering tube 5 or the like It must not be. Therefore, it is sufficient to carry out experiment or the like in advance to determine the standard of the ejection interval.

(5) Method of performing a large preliminary operation (Fig. 9)

Depending on the state of the sealing portion 9 of the plunger 6 and the measuring tube 5, the preliminary operation 1 may have to be taken large. In this case, it is also conceivable to influence the ejection operation later. Thus, as shown in Fig. 9, by performing the operation 22 of the same size in the reverse direction after the large spare operation 21, the influence on the subsequent discharge operation can be reduced. By doing so, the preliminary operation can be performed without being limited in size. This is also effective when performed in a small preliminary operation as in (1) or (4) above. It goes without saying that, if the ejection interval is short, the preliminary operation may be performed only for the first time as in the above (4).

[Industrial Availability]

INDUSTRIAL APPLICABILITY The present invention can be applied to a device in which a plunger moves while slidingly moving in a metered portion closely and discharges the liquid material in an emergency. It is effective for all kinds of liquid materials which can be discharged by the plunger, and it is effective for low viscosity materials such as water and alcohol, adhesives, liquid crystal materials, high viscosity liquids such as paste or cream industrial materials (soldering, lubricating oil, .

1: Preliminary operation
2: First preliminary operation
3: second preliminary operation
4: Discharging device
5: Weighing pipe (weighing part)
6: plunger
7:
8: Nozzle
9: Sealing part
10: Storage container
11: Switch valve
12: Screw shaft
13: Driving source (motor)
14: Control device
15: dispensing device
16: substrate
17: Table
18: XYZ drive mechanism
19: First discharge
20: Second discharge

Claims (10)

A metering section for metering the liquid material; a discharge port communicating with one end of the metering section; and a plunger for slidingly moving the inner wall of the metering section, wherein the plunger is disposed in a direction opposite to the discharge port And a discharging step of discharging the liquid material from the discharging opening by moving the plunger in the direction of the discharging opening and then stopping the discharging opening to discharge the liquid material from the discharging opening, In the liquid material discharge method,
And a preliminary operation of moving the plunger without performing the ejection of the liquid material, thereby controlling the speed of the plunger in the ejection step to be constant,
Wherein the preliminary operation includes a first operation for moving the plunger by a predetermined distance S in a direction opposite to the ejection opening and a second operation for moving the plunger in the direction of the ejection opening by a distance equal to or equal to the distance S ,
A method of dispensing a liquid material. The method according to claim 1,
Wherein the predetermined distance S is set to a distance at which the plunger is accelerated (accelerated) to a constant speed. 3. The method according to claim 1 or 2,
And repeating the first operation and the second operation until the discharging process is started after the filling process. 3. The method according to claim 1 or 2,
Wherein the first operation moves the plunger under a condition that no air bubbles are generated by the outside air sucked in the discharge port. 3. The method according to claim 1 or 2,
Wherein the second operation during the preliminary operation is an operation for accelerating the plunger toward the discharge port so that a change in the frictional resistance less affects the discharge. 3. The method according to claim 1 or 2,
Wherein the preliminary operation and the discharging step are performed continuously. A metering section for metering the liquid material; a discharge port communicating with one end of the metering section; a plunger slidingly moving with the inner wall of the metering section; a driving source for driving the plunger;
Wherein the control device is capable of performing the discharging method according to claim 1 or 2,
Dispensing device for liquid material. A table on which an object to be coated is installed,
8. An image forming apparatus comprising: a discharge device according to claim 7;
A relative movement mechanism for relatively moving the discharge device and the table,
And the liquid material. A liquid material dispensing apparatus comprising a metering section for metering a liquid material, a discharge port communicating with one end of the metering section, a plunger slidingly moving with the inner wall of the metering section, a driving source for driving the plunger, Wherein the control device is configured to execute the ejection method according to any one of claims 1 to 3. delete

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